diff --git a/src/lua/empty-test.lua b/src/lua/empty-test.lua
index 7be089b..fbbb862 100644
--- a/src/lua/empty-test.lua
+++ b/src/lua/empty-test.lua
@@ -7,18 +7,46 @@ sysbench.cmdline.options = {
     -- the default values for built-in options are currently ignored, see 
     -- https://github.com/akopytov/sysbench/issues/151
     ["cpu-max-prime"] = {"CPU maximum prime", 10000},
-    ["threads"] = {"Number of threads", 2},
-    ["histogram"] = {"Show histogram", "on"},
+    ["threads"] = {"Number of threads", 1},
+    ["histogram"] = {"Show histogram", "off"},
     ["report-interval"] = {"Report interval", 1}
 }
 
 function event()
 end
 
-function sysbench.hooks.report_intermediate(stat)
+function sysbench.hooks.report_cumulative(stat)
     local seconds = stat.time_interval
-    print(string.format("%.0f;%u;%4.2f",
-        stat.time_total, 
-        stat.threads_running,
-        stat.events / seconds))
-end
\ No newline at end of file
+    print(string.format([[
+{
+    "errors": %4.0f,
+    "events": %4.0f,
+    "latency_avg": %4.10f,
+    "latency_max": %4.10f,
+    "latency_min": %4.10f,
+    "latency_pct": %4.10f,
+    "latency_sum": %4.10f,
+    "other": %4.0f,
+    "reads": %4.0f,
+    "reconnects": %4.0f,
+    "threads_running": %4.0f,
+    "time_interval": %4.10f,
+    "time_total": %4.10f,
+    "writes": %4.0f
+}
+]], 
+    stat.errors, 
+    stat.events, 
+    stat.latency_avg, 
+    stat.latency_max, 
+    stat.latency_min, 
+    stat.latency_pct, 
+    stat.latency_sum, 
+    stat.other, 
+    stat.reads, 
+    stat.reconnects, 
+    stat.threads_running, 
+    stat.time_interval, 
+    stat.time_total, 
+    stat.writes))
+end
diff --git a/src/lua/prime-test.lua b/src/lua/prime-test.lua
index 3c8eaf6..7fe7c61 100644
--- a/src/lua/prime-test.lua
+++ b/src/lua/prime-test.lua
@@ -7,8 +7,8 @@ sysbench.cmdline.options = {
     -- the default values for built-in options are currently ignored, see 
     -- https://github.com/akopytov/sysbench/issues/151
     ["cpu-max-prime"] = {"CPU maximum prime", 10000},
-    ["threads"] = {"Number of threads", 2},
-    ["histogram"] = {"Show histogram", "on"},
+    ["threads"] = {"Number of threads", 1},
+    ["histogram"] = {"Show histogram", "off"},
     ["report-interval"] = {"Report interval", 1}
 }
 
@@ -29,10 +29,38 @@ function event()
     end
 end
 
-function sysbench.hooks.report_intermediate(stat)
+function sysbench.hooks.report_cumulative(stat)
     local seconds = stat.time_interval
-    print(string.format("%.0f;%u;%4.2f",
-        stat.time_total, 
-        stat.threads_running,
-        stat.events / seconds))
+    print(string.format([[
+{
+    "errors": %4.0f,
+    "events": %4.0f,
+    "latency_avg": %4.10f,
+    "latency_max": %4.10f,
+    "latency_min": %4.10f,
+    "latency_pct": %4.10f,
+    "latency_sum": %4.10f,
+    "other": %4.0f,
+    "reads": %4.0f,
+    "reconnects": %4.0f,
+    "threads_running": %4.0f,
+    "time_interval": %4.10f,
+    "time_total": %4.10f,
+    "writes": %4.0f
+}
+]], 
+    stat.errors, 
+    stat.events, 
+    stat.latency_avg, 
+    stat.latency_max, 
+    stat.latency_min, 
+    stat.latency_pct, 
+    stat.latency_sum, 
+    stat.other, 
+    stat.reads, 
+    stat.reconnects, 
+    stat.threads_running, 
+    stat.time_interval, 
+    stat.time_total, 
+    stat.writes))
 end